Method for operating a servomotor-driven rotation station of a layup tool of a punch press

Abstract

The present invention relates to a method for operating a servo motor (10) driven rotating station (5, 6, 7) of a lamination tool of a punch press, the method comprising the steps of: a) determining a target rotation acceleration curve of the rotating station (5, 6, 7) in an acceleration phase (A) of a rotation increment (D); b) performing a reference acceleration run of the rotating station (5, 6, 7) while providing a certain reference driving torque by the servo motor (10) or while supplying a certain reference supply current to the servo motor (10); and c) determining a reference angular velocity (ω) of the rotating station (5, 6, 7) when a certain rotation angle of the reference acceleration run is reached. ref d) determining a target angular velocity (ω) that should exist when a certain rotation angle is reached from the target rotation acceleration curve; soll ) and e) determining the reference angular velocity (ω) known from the reference acceleration run. ref ) and the drive torque of the servo motor (10), the target angular velocity (ω soll f) calculating a target drive torque for the servo motor that results in a rotation increment (D) of rotational speed; and f) accelerating the rotating stations (5, 6, 7) with the servo motor (10) in normal production operation during the acceleration phase (A) of the rotation increment (D) while providing the target drive torque by the servo motor (10).

Description

[Technical field]

[0001] The invention relates to a method for operating a servomotor-driven rotating station of a layup tool of a punch press, and to a punch press having a layup tool with a servomotor-driven rotating station according to the preambles of the independent claims. [Background technology]

[0002] In the large-scale series production of electric motors, a punching process is essential to produce the sheet metal packs of rotors and stators. In this process, individual sheets are punched from a piece of metal in a punch press, stacked in a stamping die and joined together to form a sheet pack of the desired height. To prevent variations in sheet thickness across the width of the stack from the top of the sheets to the skewed stack, the stack of sheets is rotated by a certain increment before each new sheet is placed on the stack by the rotation station of the respective stacking tool. In this situation, any variations in sheet thickness are automatically compensated for during packaging. However, with today's standard punching speeds and servo-motor driven rotation stations, this rotation is difficult because the sheet packs have a relatively high mass inertia and very little time is available for the rotation station to accelerate and decelerate each sheet pack.

[0003] In particular, when both the rotor and the stator sheet packs of an electric motor are manufactured on a punching press with the same die, the operating parameters for the rotating stations of the individual sheet packs are very different, since the masses and the moments of rotational inertia are very different due to the different weights and diameters of the sheet packs. For example, it is not uncommon that the rotational inertia of the rotating station with the rotor sheet pack is 10 to 2 times smaller than that of the rotating station with the associated stator sheet pack. In practice, this means that it takes a considerable amount of time and skill to repeatedly adjust the rotating station to the respective production job, and nevertheless, in most cases the rotating station is operated with a suboptimal motion profile. In this case, unnecessarily high accelerations and / or decelerations are used, since it is not possible to set a specific motion profile and it is necessary to ensure that each rotation increment can always be completed in the available time. However, this also consumes energy unnecessarily and causes unnecessary wear on the production equipment. In addition, unnecessarily high acceleration values ​​can lead to vibrations in the system, which has a negative effect on the production result. Summary of the Invention [Problem to be solved by the invention]

[0004] The object is therefore to provide a technical solution which does not have or at least partially avoids the above-mentioned disadvantages of the current state of the art. [Means for solving the problem]

[0005] This object is solved by a method and a punch press according to the independent claims.

[0006] According to these, a first aspect of the invention relates to a method of operating a servo motor driven rotation station of a stacking tool of a punch press.

[0007] In this case, a target rotation acceleration process of the rotating station is defined in the acceleration phase of the rotation increment, advantageously such that the most energy-efficient movement profile possible is provided without unnecessarily large accelerations.

[0008] One or more of the following target parameters are determined from the target rotational acceleration curve: - a target rotational acceleration that must exist over a certain rotational range, - the target angular velocity that must exist when a certain angle of rotation is reached, - a target rotation time that must have elapsed when a certain rotation angle is reached, - A target rotation angle that must exist when a certain rotation time is reached.

[0009] In addition, a reference acceleration run of the rotating station is performed to determine the dynamic behavior of the rotating station, i.e., the relationship between the drive torque of the servo motor and / or the supply current of the servo motor and the rotational acceleration of the rotating station, which here can also be represented by the angular velocity when a certain rotation angle is reached, the rotation time until a certain rotation angle is reached, and / or the rotation angle after a certain rotation time is reached.

[0010] For a reference acceleration run, a rotating station provided with a stack of sheets or with a "dummy" representative of this stack of sheets is accelerated by the servo motor while providing a specific reference drive torque or while supplying a specific reference supply current to the servo motor during a reference acceleration run, and one or more of the following reference parameters of this reference acceleration run are determined: - the reference rotational acceleration of a rotating station or a servo motor achieved over a certain rotational range, - the reference angular velocity of a rotating station or a servo motor when a certain angle of rotation is reached, - the reference rotation time elapsed until a certain rotation angle is reached, - A reference rotation angle that exists after a certain rotation time has elapsed.

[0011] Using the determined target parameters and the determined reference parameters, a target drive torque and / or a target supply current of the servo motor are then calculated, which will result in a target rotation acceleration in a certain rotation range, a target angular velocity when a target rotation angle is reached, a target rotation time when a certain rotation angle is reached, and / or a target rotation angle after a certain rotation time has elapsed in the intended operation, via the relationship between the reference rotation acceleration, the reference angular velocity, the reference rotation time and / or the reference rotation angle, which are known from the reference acceleration operation, and the drive torque and / or the supply current of the servo motor.

[0012] The determination of the target parameters and the determination of the reference parameters can basically be performed independently of each other and therefore do not require a certain sequence. However, it is advantageous for easy processing of the target parameters and the reference parameters if the same certain rotation range, the same certain rotation angle and / or the same certain rotation time are used for their determination. The target parameters and the reference parameters that are determined or established for a certain rotation range, rotation angle and / or rotation time that are not the same can also be evaluated or compared via the known relationship between the drive torque of the servo motor and / or the supply current of the servo motor and the rotation acceleration, the angular velocity, the rotation time and / or the rotation angle.

[0013] Then, in normal production operation, the rotating station is accelerated by the servo motor in an acceleration phase of each rotation increment while a target drive torque is provided by the servo motor or while a target supply current is supplied to the servo motor.

[0014] The method of the present invention allows the motion profiles of the servo motor driven processing stations of a lamination tool to be set up and optimized in a short time, without requiring much skill, and using actual "teach-in" movements.

[0015] Advantageously, a target rotational acceleration curve is defined, in which the rotating stations are accelerated essentially uniformly during the acceleration phase of the rotational increments. "Essentially uniform" should be understood in this document as meaning that the acceleration is uniform over the majority of the acceleration phase. However, it may be entirely conceivable and desirable to define a lower acceleration at the beginning and end of the acceleration phase, or a smooth transition from a stop at the beginning and end of the acceleration phase to a deceleration phase.

[0016] It is also preferred that the reference acceleration run is performed by providing a nominal drive torque of the servo motor as the reference drive torque or by supplying the servo motor with a nominal supply current as the reference supply current.

[0017] It thus becomes immediately evident if the specified target values ​​cannot be realized with the existing servo motors, and it is then necessary to reduce the number of strokes of the press accordingly or to use more powerful servo motors.

[0018] In a preferred embodiment of the method, the rotation angle of the rotation station is determined for each rotation increment and the reference acceleration run is performed over a range of the rotation angle, for example over half or the whole rotation angle.

[0019] In another preferred embodiment of the method, the available rotation time is determined for each rotation increment and the reference acceleration maneuver is performed over a range of rotation times, for example over half or all of the available rotation time.

[0020] Depending on which parameters are used to calculate the target drive torque or the target supply current of the servo motor, one or other embodiment of the method may be more advantageous.

[0021] In a further preferred embodiment of the method of the invention, both the available rotation time per rotation increment and the rotation angle of the rotation station per rotation increment are determined and a target rotation acceleration curve is defined, according to which half the rotation angle is reached at or after the end of half the available rotation time.

[0022] A target rotation acceleration curve is defined, according to which the acceleration phase of the rotation increment is preferably completed when or after half the rotation angle is reached.

[0023] Thus, an energy efficient motion profile without unnecessarily large accelerations is preferred.

[0024] In a variant of the method in which the available rotation time per rotation increment is determined, it is advantageous to determine this rotation time per rotation increment in such a way that the theoretically available rotation time per rotation increment is reduced by a period of time provided for settling the system at the end of the rotational movement, this ensuring that any system vibrations have been damped before the next sheet is laid down on the stack of sheets at the rotating station.

[0025] In a variant of the method in which the available rotation time per rotation increment is determined, it is also advantageous if the available rotation time per rotation increment or the theoretically available rotation time per rotation increment is determined depending on the target stroke rate of the press or depending on the current stroke rate of the press. In the latter case, the rotation acceleration curve or the motion profile of the rotating station can be dynamically adapted to the press speed and a motion profile optimized in terms of energy and wear can be used for the operating situation.

[0026] In yet another preferred embodiment of the method, the target rotational acceleration of the rotating station is defined over the entire rotation increment, i.e. for the acceleration and deceleration phases, such that the deceleration phase preferably starts immediately after the acceleration phase. This allows the entire available rotation time to be used for acceleration and deceleration, resulting in a particularly energy-efficient motion profile when the available time is roughly divided in half between the acceleration and deceleration phases.

[0027] It is preferred to determine a target rotational deceleration that should be present in the deceleration phase according to said target rotational acceleration curve. Using the determined target rotational deceleration and the determined reference parameters, a target brake torque and / or a target brake supply current of the servo motor is calculated, via a relationship between the reference rotational acceleration, the reference angular velocity, the reference rotation time and / or the reference rotational speed, which is known from the reference acceleration operation, such that the target brake torque and / or the target brake supply current, the target rotational deceleration occurs as intended in the operation. The rotation of the rotating station by means of the servo motor is then decelerated in a deceleration phase of the rotation increment by providing the target brake torque by the servo motor or supplying the target brake supply current to the servo motor.

[0028] In this way, the deceleration stages of the rotational increments can also be targeted and optimized via a "teach-in" operation in a very short time and without requiring much skill.

[0029] A further optimization is possible if, if possible, the friction losses and / or the supply current corresponding to the friction losses are determined for the rotating station before the target rotational speed of the rotating station is defined and taken into account when defining the target rotational speed of the rotating station. This can be done, for example, by determining a constant supply current or a constant drive torque of the servo motor when the rotating station rotates slowly forwards and backwards.

[0030] It is advantageous to take into account the friction loss brake torque or a corresponding parameter of the rotating station, so that during the transition from the acceleration phase to the deceleration phase of the rotation increment, the target rotation acceleration curve shows a sharp drop in the angular velocity as a result of the friction loss brake torque. Taking this aspect into account, the target rotation acceleration curve can be optimized, so that the acceleration phase and / or the deceleration phase can be designed to be even "smoother".

[0031] It is also preferred that the friction loss brake torque of the rotating station and / or the supply current corresponding to the friction loss are determined before calculating the target brake torque and / or the target brake supply current of the servo motor and are taken into account accordingly when calculating the target brake torque and / or the target brake supply current of the servo motor.

[0032] In yet another preferred embodiment of the method, the target rotational acceleration curve of the rotating station is set such that the target rotational deceleration in the deceleration phase of the rotational increment is numerically smaller than the target rotational acceleration in the acceleration phase of the rotational increment, which is favorable for damping of any oscillations at the end of the rotational increment.

[0033] Advantageously, the friction loss brake torque of the rotating station or the supply current corresponding to the friction loss brake torque is determined by a test run, in which the rotating station is rotated by the servo motor preferably at a uniform angular speed, in particular by a rotation angle preferably corresponding to the rotation angle of the rotating station per rotation increment, in such a way that realistic operating conditions prevail when determining the friction loss brake torque of the rotating station or the supply current corresponding to the friction loss brake torque.

[0034] A second aspect of the invention relates to a punch press having a lamination tool with a rotation station driven by a servo motor, the punch press having a controller for operating the rotation station in the manner described above according to the first aspect of the invention.

[0035] Preferably, the control system that operates the rotating station is integrated into the press control system. This makes it possible to have a uniform and consistent system, and also the existing control mechanisms for the press control can be used to control the rotating station.

[0036] Further preferred embodiments of the invention are evident from the dependent claims and from the description that follows with reference to the drawings, whereby further preferred embodiments of the invention are shown below. [Brief description of the drawings]

[0037] [Figure 1] FIG. 2 is a simplified diagram of the lower part of a progressive punching tool for the manufacture of three different sheet metal laminations of an electric motor. [Diagram 2] FIG. 2 is a top view of a three-sheet stack produced using the progressive punch tool according to FIG. 1; [Diagram 3] 2 is a vertical section across the band advance direction through the progressive punch tool of FIG. 1 in the region of one of the rotation stations; FIG. [Figure 4] A target rotation acceleration curve defined in the form of the angular velocity of the rotating station over a rotation increment. [Diagram 5] 1 is a curve of the angular velocity of a rotating station over time during a reference acceleration run. [Figure 6] 4 is a curve of friction losses brake torque of a rotating station over time during a test run for their determination. [Figure 7] is the angular velocity of a defined target rotation acceleration curve of the first rotating station 5 over the entire rotation increment, taking into account the determined friction loss brake torque. [Figure 8] is the angular velocity of a defined target rotation acceleration curve of the second rotating station 6 over the entire rotation increment when taking into account the determined friction loss brake torque. [Figure 9]is the angular velocity of a defined target rotation acceleration curve of the third rotating station 7 over the entire rotation increment, taking into account the determined friction loss brake torque. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Figure 1 shows a simplified view of the lower part of a progressive die cutting tool 1 for manufacturing three different sheet metal laminations 2, 3, 4 of an electric motor, shown in top view in Figure 2. The first sheet metal lamination 2 forms the rotor of the motor, the second sheet metal lamination 3 forms the stator star of the motor and the third sheet metal lamination 4 forms the stator ring of the motor.

[0039] The progressive punching tool 1 has three rotation stations, indicated by the references 5, 6 and 7. In the present case, the band advance direction A through the tool 1 runs from left to right.

[0040] The manufacturing sequence on the tool 1 starts with the smallest part: thus the rotor sheet metal lamination 2 is laid up in a first rotating station 5, the stator star sheet metal lamination 3 is laid up in a second rotating station 6 and the stator ring sheet metal lamination 4 is laid up in a third rotating station 7.

[0041] The sheet-metal connection is achieved here using the so-called clinching process, which is known to the person skilled in the art and therefore does not need to be described in more detail here, an alternative to this is to join the individual sheets by laser welding, baking paint or glue.

[0042] FIG. 3 shows a vertical section transverse to the direction of band advance through the progressive punch tool 1 in the region of the third rotation station 7 .

[0043] The stack of sheets 2, 3, 4 must be rotated during laying because there may be variations in sheet thickness across the width of the processed sheet strip, which, if laid down at the same point, would always result in a skewed stack of sheets. Rotation of the stack of sheets causes the estimated sheet metal thickness variations to move in a circular motion, resulting in a cylindrical stack.

[0044] The rotor sheet stack 2 has 10 pitches, which results in a rotation angle of 36° for this sheet stack 2 per rotation increment D. The stator star has 12 beams, which results in a rotation angle of 30° for the stacked cores 3 of the stator star and the stacked cores 4 of the associated stator rings per twist increment D. The rotation stations 5, 6, 7 are rotated by servo motors 10 via toothed belt drives, each of which has, for example, a power of 3000 W and a nominal torque of 19.1 Nm. The stack height is monitored and controlled by the count of the individual sheets and the measured band thickness. If the stack is high enough, a switchable punch is used to cut out the interleaves for the clinching process, so that a gap is formed before the stacking of the next stack is started. The completed stack, which in the situation shown in FIG. 3 is a stator ring sheet metal stack 4, falls downwards onto the conveyor belt 8, which guides it away from the tool 1 at right angles to the band travel direction.

[0045] The rotating stations 5, 6, 7 also act as sheet stack brakes. They must provide the necessary resistance as the individual sheets are joined. An important quality feature of the finished sheet stacks 2, 3, 4 is their holding power. This is repeatedly checked on random samples during the production process.

[0046] In the present case, the progressive punching tool 1 is mounted on an automatic punching machine operated at 480 strokes / min. A window covering 300° crank angle is available for rotating the rotating stations 5, 6, 7. A theoretical rotation time t of 104 ms is therefore available for each rotation increment D of 36° or 30°. To ensure that at the end of the rotational movement there is still enough time to de-energize or switch the current of the drive motor 10 and to damp any vibrations so that the catch pin or pins can make a fine adjustment of the rotating station, the theoretically available rotation time t of 104 ms per rotation increment D is broken down into a time span t of 4 ms. idle , and an available rotation time t per rotation increment D of 100 ms is assumed for the determination of the target acceleration curves of the rotation stations 5, 6, 7.

[0047] The servo motor 10 must accelerate different external mass inertias over a wide range, which depend on the fourth power of the outer radius of the rotating station.

[0048] In order to determine the target parameters, the target rotation acceleration curves of the rotating stations 5, 6, 7 are set accordingly. To achieve the most energy-efficient and material-saving rotation of the sheet metal stack possible by the rotating stations 5, 6, 7, the available rotation time t of 100 ms is evenly divided between the acceleration phase A and the deceleration phase B of a rotation increment D such that they immediately follow each other. In other words, acceleration occurs over the first half and deceleration occurs over the second half of the respective rotation angle per rotation increment D. In this way, unnecessarily strong accelerations and decelerations are avoided.

[0049] Thus, the target rotation acceleration curves determined for the rotation stations 5, 6, 7 are given in FIG. soll Angular velocity ω over (ms) soll (s -1 ) is shown. As can be seen, the acceleration time t A is 50 ms, and the deceleration time tB is also 50 ms, and the settling time t idle As can be seen, in the first rotation station 5 of the rotor sheet pack 2, after a rotation time of 50 ms or a rotation angle of 18°, the -1 Angular velocity ω soll must be achieved, while in the second rotating station 6 of the stator star sheet metal lamination 3 and in the third rotating station 7 of the stator ring sheet metal lamination 4, after a rotation time of 50 ms or a rotation angle of 15° in each case, a rotation time of 10.5 s -1 The same angular velocity ω soll must be achieved. The acceleration and deceleration in the first rotation station 5 of the rotor sheet stack 2 must be correspondingly larger. This is due to the larger rotation angle per rotation increment of 36° instead of 30°. The specified target rotation acceleration curve is symmetric for the acceleration A and deceleration B stages, so that the target parameters for the deceleration B stage are the inverse of the target parameters for the acceleration A stage.

[0050] The rotating stations 5, 6, 7, each fully equipped with a sheet pack 2, 3, 4, and completely filled with sheet packs 2, 3, 4, perform a reference acceleration run over a reference rotation angle corresponding to half the rotation angle of the rotating station per rotation increment D. The reference rotation angle of the first rotating station 5 is therefore 18° and for the second rotating station 6 and the third rotating station 7 it is 15° in each case. The servo motor 10 is driven with a nominal torque of 19.1 Nm and a reference angular speed ω ref Each of the rotation stations 5, 6, and 7 is driven by the reference rotation angle t ref is recorded.

[0051] The reference acceleration curves thus determined for the rotation stations 5, 6, 7 are shown in FIG. ref Angular velocity ω over (ms) ref (s -1 ) are used.

[0052] As can be seen, the first rotating station 5 for the rotor ring sheet metal lamination 2 has a reference rotation time t ref After reaching the reference rotation angle, the reference rotation angle is 73.1s -1 The reference angular velocity ω ref while the second rotating station 6 for the stator ring sheet metal laminations 3 has a reference rotation time t ref For this you need 15.1s -1 The reference angular velocity ω ref and the third rotating station 7 for the stator ring sheet metal laminations 3 reaches a reference rotation time t ref Requires 12.9s -1 The reference angular velocity ω ref Achieve this.

[0053] Reference angular velocity ω for rotation stations 5, 6, and 7 ref or reference rotation time t ref and the reference drive torque of 19.1 Nm of the associated servo motor 10, the target drive torque of the servo motor 10 is then calculated, resulting in the respective target angular velocity ω soll and the target rotation time t soll is obtained.

[0054] For this purpose, each target parameter ω soll , t soll and the reference parameter ω ref , t ref are set relative to one another and the nominal drive torque is multiplied by this ratio, which is shown below for the first rotating station 5 by way of example.

[0055] The target angular velocity ω determined for the rotating station 5 after a rotation angle of 18° soll is 12.6s -1 The reference angular velocity ω determined using the reference acceleration run of this rotation station 5 after a rotation angle of 18° is ref is 73.1s -1 The determined target angular velocity ω sollThe reference angular velocity ω is determined as ref The ratio of t to 0.172 is multiplied by the nominal drive torque of the servo motor 10 of 19.1 Nm, resulting in a target drive torque of the first rotating station 5 for the rotor sheet metal lamination 2 of 3.28 Nm. The nominal rotation time t determined for the first rotating station 5 of 8.6 ms ref However, the determined target rotation time t soll The same result is obtained when relating the ratio of 0.172 to the nominal drive torque of the servo motor 10, 19.1 Nm.

[0056] For the second rotating station 6 of the stator star sheet metal lamination 3, this calculation results in a target drive torque of the servo motor 10 of 13.23 Nm and for the third rotating station 7 of the stator ring sheet metal lamination 4 a target drive torque of the servo motor 10 of 15.54 Nm. The target drive torque calculated for the acceleration phase A also represents the target brake torque for the deceleration phase B, simply with the opposite force direction.

[0057] In a variant of the above-mentioned "teach-in" operation, in addition to the reference acceleration run, further test runs are carried out to determine the friction loss brake torque (friction torque) M (Nm) of the individual rotating stations 5, 6, 7, which are taken into account when determining the target rotational acceleration run of the rotating stations 5, 6, 7.

[0058] For this purpose, the rotating stations 5, 6, 7 having the servo motors 10 are rotated slowly in both directions by half a rotation angle. The friction torque M is determined by detecting the supply current or drive torque of the servo motors. If the supply current is detected, the drive torque or friction torque is determined from the known relationship between the supply current and drive torque of the servo motors 10.

[0059] FIG. 6 shows the curves of friction losses brake torque M (Nm) for the rotating stations 5, 6, 7 determined during the test run over time t (s).

[0060] The friction torques M thus determined, i.e. 0.5 Nm for the first rotating station 5, 1.4 Nm for the second rotating station 6 and 1.2 Nm for the third rotating station 7, are now subtracted twice each from the acceleration torques and thus used as deceleration torques. Using the relationships known from the reference acceleration run, these deceleration torques can be converted into angular velocities for the definition of the target rotational acceleration curve according to FIG. 4 and subtracted accordingly in the deceleration phase B.

[0061] 7 to 9 show the target rotational acceleration curves of the individual rotating stations 5, 6, 7 over the rotational increment D thus determined, taking into account the determined friction loss brake torque M. As can be seen, in the case of these target rotational acceleration curves the deceleration phase B is even smoother than that shown in FIG. 4. When calculating the respective target brake torque for the deceleration phase B, the target angular speed ω ... soll By assuming the following, the respective friction losses of the brake torque M are taken into account.

[0062] The above-mentioned process steps are performed automatically by the control system of the automatic punching press when the corresponding "teach-in" functions are used, i.e. during normal operation of the automatic punching press the rotating stations 5, 6, 7 of the progressive punching tool 1 are controlled such that the servo motors 10 provide respective target drive and brake torques for the rotation of the rotating stations 5, 6, 7.

[0063] It is also envisaged that after the actual "teach-in", the available rotation time t per rotation increment D, which depends on the stroke rate of the press, is continuously determined, the target rotation acceleration curve is adjusted accordingly, and new target drive and brake torques are calculated with the known parameters from the reference acceleration run and used for the control. In this way, the rotation stations 5, 6, 7 can be automatically optimally operated at any stroke rate of the punch press.

[0064] Although preferred embodiments of the present invention have been described herein, it is to be expressly noted that the invention is not limited thereto and may be otherwise practiced within the scope of the claims which follow.

Claims

1. A method for operating a servomotor (10) driven rotation station (5, 6, 7) of a lamination tool of a punch press, comprising the steps of: a) determining a target rotation acceleration curve for said rotation stations (5, 6, 7) during an acceleration phase (A) of rotation increments (D); b) performing a reference acceleration operation of said rotating stations (5, 6, 7) while providing a constant reference driving torque by said servo motor (10) or while supplying said servo motor (10) with a constant reference supply current; c) the following reference parameters of said reference acceleration run: c1) a reference rotational acceleration of said rotating station (5, 6, 7) or of said servo motor (10) achieved over a certain rotational range; c2) the reference angular velocity (ω) of the rotating station (5, 6, 7) or the servo motor (10) when a certain rotation angle is reached ｒｅｆ ), c3) The reference rotation time (t ｒｅｆ ), c4) A reference rotation angle after a certain rotation time has elapsed determining one or more of: d) from the target rotation acceleration curve, the following target parameters: d1) a target rotational acceleration that must exist within a certain rotational range; d2) A target angular velocity (ω ｓｏｌｌ ), d3) A target rotation time (t ｓｏｌｌ ), d4) A target rotation angle that should exist when a certain rotation time is reached. determining one or more of: e) the reference rotational acceleration, the reference angular velocity (ω ｒｅｆ ), the reference rotation time (t ｒｅｆ ) and / or the reference rotation angle, and the drive torque of the servo motor (10) and / or the supply current of the servo motor (10) from the relationship, the target rotation acceleration, the target angular velocity (ω ｓｏｌｌ ), the target rotation time (t ｓｏｌｌ ) and / or a target drive torque and / or a target supply current of the servo motor at which the target rotation angle is generated; and then f) accelerating said rotating stations (5, 6, 7) with said servo motor (10) in said acceleration phase (A) of said rotation increments (D) in normal production operation while providing said target drive torque by said servo motor (10) or while supplying said target supply current to said servo motor (10); A method comprising:

2. 2. The method according to claim 1, wherein a target rotational acceleration curve is determined, according to which the rotating stations (5, 6, 7) are accelerated substantially uniformly in the acceleration phases (A) of the rotational increments (D).

3. 3. The method according to claim 1 or 2, wherein the reference acceleration operation is performed while providing a nominal drive torque of the servo motor (10) as the reference drive torque or while supplying a nominal supply current to the servo motor (10) as the reference supply current.

4. 4. The method according to claim 1, wherein the rotation angle of the rotation station is determined every rotation increment (D) and the reference acceleration run is performed over a certain portion of the rotation angle, in particular over half of the rotation angle.

5. 4. The method according to claim 1, wherein an available rotation time for each rotation increment (D) is determined and the reference acceleration run is performed over a certain portion of the rotation time, in particular over half of the available rotation time.

6. 6. The method according to claim 1, wherein the available rotation time per rotation increment (D) and the rotation angle of the rotation station per rotation increment (D) are determined and a target rotation acceleration curve is defined according to which half of the rotation angle is reached at or after the end of half of the available rotation time.

7. 7. The method according to claim 6, wherein a target rotation acceleration curve is defined according to which the acceleration phase of the rotation increment (D) is completed when or after half the rotation angle is reached.

8. The available rotation time per rotation increment (D) is determined by the time period (t ｉｄｌｅ 8. The method according to claim 5, wherein the number of occurrences of the sigma-based ...

9. 9. Method according to any one of claims 5 to 8, wherein the available rotation time per rotation increment (D) or the theoretically available rotation time per rotation increment (D) is determined as a function of a target stroke rate of the press or as a function of a current stroke rate of the press.

10. 10. The method according to claim 1, wherein the target rotational acceleration curve of the rotating station is defined over a rotational increment (D), in particular such that a deceleration phase (B) starts immediately after the acceleration phase (A).

11. g) determining a target rotational deceleration that should be present in the deceleration phase (B) according to the target rotational acceleration curve; h) the reference rotational acceleration, the reference angular velocity (ω ｒｅｆ ), the reference rotation time (t ｒｅｆ ) and / or calculating a target brake torque and / or a target brake supply current of the servo motor (10) at which the target rotational deceleration occurs from a relationship between the reference rotation angle and the drive torque of the servo motor (10) and / or the supply current of the servo motor (10); i) slowing down the rotation of the rotating stations (5, 6, 7) by the servo motor (10) during the deceleration phase (B) of the rotation increment (D) by providing the target brake torque by the servo motor (10) or by supplying the target brake supply current to the servo motor (10); The method of claim 10 further comprising:

12. 12. The method according to claim 11, in particular prior to determining the target rotational acceleration curve of the rotating station (5, 6, 7), a friction loss brake torque of the rotating station (5, 6, 7) and / or a supply current corresponding to said friction loss brake torque are determined and taken into account in determining the target rotational acceleration curve of the rotating station (5, 6, 7), in particular such that as a result of said friction loss brake torque there is a sharp drop in angular velocity during the transition from the acceleration phase (A) to the deceleration phase (B) of the rotation increment (D).

13. 13. The method according to claim 12, wherein the friction loss brake torque and / or the supply current corresponding to the friction loss brake torque of the rotating station (5, 6, 7) is calculated prior to calculating the target brake torque and / or the target brake supply current of the servo motor (10) and is taken into account in calculating the target brake torque and / or the target brake supply current of the servo motor.

14. 14. The method according to claim 11, wherein the target rotational acceleration curves of the rotation stations (5, 6, 7) are determined such that the target rotational deceleration in the deceleration phase (B) of the rotation increment (D) is numerically smaller than the target rotational acceleration in the acceleration phase of the rotation increment (D).

15. 14. The method according to claim 12 or 13, wherein the friction loss brake torque of the rotating stations (5, 6, 7) and / or the supply current corresponding to the friction loss brake torque are determined by a test run, during which the rotating stations (5, 6, 7) are rotated by the servo motor (10), in particular with a uniform angular speed, in particular by a rotation angle corresponding to half the rotation angle of the rotating stations (5, 6, 7) per rotation increment (D), in particular back and forth.

16. A punch press having a lamination tool with rotating stations (5, 6, 7) driven by servo motors (10), the punch press having a control for operating said rotating stations (5, 6, 7) according to the method according to any one of claims 1 to 15.

17. 17. A punch press according to claim 16, wherein the controls for operating the rotation stations (5, 6, 7) are integrated into the control of the press.

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